FCC ID 2AVJD-K521B
Wireless earphones
by Shenzhen Ruianyuan Electronic Technology Co., Ltd.
Grantee Code: 2AVJD Product Code: K521B
Latest application date: 2025-11-27
FCC ID Device Details
| FCC ID | 2AVJD-K521B |
|---|---|
| Mirrors | fcc.id | gov | fccid.ai |
| Grantee Code | 2AVJD |
| Product Code | K521B |
| Applicant Business | Shenzhen Ruianyuan Electronic Technology Co., Ltd. 🇨🇳 |
| Equipment Class | Wireless earphones |
| Test Firm | Dongguan Yaxu (AiT) Technology Limited |
Operating Frequencies
| Frequency Range | Application Purpose | Final Action Date |
|---|---|---|
| 2402-2480 MHz | Original Equipment | 2025-11-27 |
Exhibits
| Document | Type | Available | File |
|---|---|---|---|
| User Manual | Users Manual | 2025-11-27 | PDF 1.8 MB |
| Internal Photos | Internal Photos | 2025-11-27 | PDF 4 MB |
| External Photos | External Photos | 2025-11-27 | PDF 2.6 MB |
| FCC ID Label | ID Label/Location Info | 2025-11-27 | PDF 84.1 KB |
| Test Setup Photos | Test Setup Photos | 2025-11-27 | PDF 1.5 MB |
| AiTDG-250829001W1_Test Report-BT | Test Report | 2025-11-27 | PDF 974.2 KB |
| Antenna Specification | Test Report | 2025-11-27 | PDF 845.5 KB |
| Appendix A RF Test Data for BT_Part1 | Test Report | 2025-11-27 | PDF 6 MB |
| Appendix A RF Test Data for BT_Part2 | Test Report | 2025-11-27 | PDF 5.9 MB |
| 2AVJD-K521B US_Agent | Attestation Statements | 2025-11-27 | PDF 146.8 KB |
| USA-CoveredEquipmentLetter-Combined_V1.1 | Attestation Statements | 2025-11-27 | PDF 123.8 KB |
| FCC Declaration Letter TWS left&Right | Cover Letter(s) | 2025-11-27 | PDF 81.3 KB |
| USA-ConfidentialityRequestLetter_V0.1 | Cover Letter(s) | 2025-11-27 | PDF 103.6 KB |
| AiTDG-250829001W2_FCC RF EXPOSURE 0cm | RF Exposure Info | 2025-11-27 | PDF 326 KB |
| Block Diagram Metadata only | Block Diagram | PDF 45.6 KB | |
| Schematic Metadata only | Schematics | PDF 261.7 KB | |
| Operation Description Metadata only | Operational Description | PDF 158.9 KB | |
| USA-DueDigilenceLetter_V0.1 Metadata only | Operational Description | PDF 87.1 KB |
Application Information
| Application ID | 2Hdma5vNLlJtBcs+9GZ1AQ== |
|---|---|
| Final Action Date | 2025-11-27 |
| Application Purpose | Original Equipment |
| Applicant FRN | 0029089190 |
| Model | K521B |
| Frequency Range | 2402-2480 MHz |
| Equipment Class | DSS - Part 15 Spread Spectrum Transmitter |
| Device Description | Wireless earphones |
| Responsible Party | Meizhen Lin, 2880644089@qq.com  , 13502890859 |
| Test Firm | Coin Tang, Dongguan Yaxu (AiT) Technology Limited, info@aitek.org.cn  , 86-0769-82020499-21 |
| TCB Email | o.kneip@kl-certification.de  |
| TCB Scope | A4: UNII devices & low power transmitters using spread spectrum techniques |
| Short-Term Confidentiality | No |
| Long-Term Confidentiality | Yes |
| Modular Equipment | Does not apply |
| Composite Device | No |
| Cognitive Radio | No |
| Authorization Waiver | No |
| Authorization Waiver Approved | No |
| Section 5301 Certification | Yes |
| Related OET Knowledge DataBase Inquiry | No |
Applications
| Application ID | Date | Purpose |
|---|---|---|
| 2Hdma5vNLlJtBcs+9GZ1AQ== | 2025-11-27 | Original Equipment |
Equipment Authorization
| Frequency | Output | Rules |
|---|---|---|
| 2402-2480 MHz | 0.0019 | 15C |
Grants
TCB Grant - Application 2Hdma5vNLlJtBcs+9GZ1AQ==
| TCB | GRANT OF EQUIPMENT AUTHORIZATION |
TCB |
| Certification | ||
| Issued Under the Authority of the | ||
| Federal Communications Commission | ||
| By: |
|
KL-Certification GmbH Heinrich-Hertz-Allee 7 St. Ingbert, 66386 Germany |
Date of Grant: 11/27/2025 Application Dated: 11/27/2025 |
| Shenzhen Ruianyuan Electronic Technology Co., Ltd. |
| Floor 4, building 5, tumao industrial park |
| hebei industrial zone, longhua district |
| Shenzhen, China |
| Attention: Meizhen Lin , |
| NOT TRANSFERABLE |
| EQUIPMENT AUTHORIZATION is hereby issued to the named GRANTEE, and is VALID ONLY for the equipment identified hereon for use under the Commission's Rules and Regulations listed below. |
| FCC IDENTIFIER: | 2AVJD-K521B |
| Name of Grantee: | Shenzhen Ruianyuan Electronic Technology Co., Ltd. |
| Equipment Class: | Part 15 Spread Spectrum Transmitter |
| Notes: | Wireless earphones |
| Grant Notes | FCC Rule Parts | Frequency Range (MHZ) | Output Watts | Frequency Tolerance | Emission Designator |
| 15C | 2402.0 - 2480.0 | 0.0019 |
| Output Power listed is peak conducted. |